This library contains two modules, continuations and continuations-used.

The former provides some syntactic sugar to Marc Feeley's continuation interface. In this interface, continuations are a datatype separate from procedures. Hence it provides a continuation? predicate. I've stripped the prefix from the procedures continuation-capture and continuation-graft and renamed continuation-return throw. This latter procedure is accompanied in this module by a macro named catch, so that the usual catch-throw-semantics of other languages is available. But note, that in this pattern, the continuation is a Scheme object, and like every Scheme object it has indefinite extent, hence can be exported, saved in other data-structures etc. So this pattern is much more powerful than the corresponding pattern in other languages.

Some other procedures are provided as well, in particular continuation->procedure, which does what the name says, and continuations, which provides offline documentation to the module. Like in my other modules, the call (continuations) lists the exported symbols, and (continuations sym) provides documentation of the exported symbol sym.

And then there is the infamous goto, which albeit dangerous is sometimes useful, e.g. in backtracking ....

Moreover, another interface to continuations is provided, recommended by Matt Might, and that in two flavors, with continuations, checked by continuation?, and escape procedures, checked by escape-procedure?. This makes possible code written in an idiom similar to the setjmp-longjmp-pair in C.

The second module, continuations-used, provides some applications of the continuations module.

The same as call/cc but with a different datatype: Captures the current continuation as a continuation datatype (contrary to a procedure datatype in call/cc) and calls proc with that continuation as its only argument.

The same as let/cc of miscmacros but with a different datatype: Binds the cont variable to the current continuation as a continuation and executes the body xpr .... in this context. Typically used as follows

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